When Lillian Thresa Shortill was born on 11 May 1883, in Johnson, Wyoming, United States, her father, Thomas Patrick Shortill, was 49 and her mother, Catherine Agnes Cannon, was 44. She married Glenford Gordon Peterson on 7 May 1904. They were the parents of at least 2 sons and 3 daughters. She lived in Buffalo, Johnson, Wyoming, United States for about 20 years and Los Angeles, Los Angeles, California, United States in 1930. She died in 1973, at the age of 90, and was buried in Lewiston, Nez Perce, Idaho, United States.